DE 27 50 6 42 C2 discloses a method and an apparatus for producing any desired blanks from elastomeric material. As disclosed, in order to remove a core, the product is put onto a carpet having a high coefficient of friction, and a longitudinal movement is superimposed on the carpet. The carpet is preferably made of rubber grooved in the transverse direction. This reference further describes how the core, before the product is applied, can be covered with a suitable separating agent, such as a silicone solution for example, and how compressed air is introduced into the product in order to achieve a certain enlargement of the product.
DE 21 40 9 56 C3 describes an apparatus for producing elbow hoses on mandrels. In this apparatus, an elbow blank is pushed onto the mandrel by means of a push cylinder. The push cylinder, which can be attached to the rear end face of the elbow blank in a pressure-tight manner, ensures that, when the elbow blank is pushed onto the mandrel, the air contained in the blank volume does not escape past the push cylinder but leads to an air cushion between the elbow blank and the mandrel. This air cushion facilitates the push-on operation.